Protecting Workers When there are Power Outages

Employers should have an adequate emergency action plan (section 3220) to be prepared for and ensure for safety during power outages.

If generators are used at the worksite, employers must ensure they comply with the following safety requirements:

  • Keep generators outdoors (sections 3662, 5141, 5155 and 5146). When in use, generators produce carbon monoxide gas, which is colorless, odorless, tasteless and potentially lethal.
  • Generators should be properly grounded (except for portable and vehicle-mounted generators under certain circumstances, provided certain other safety measures are taken) (sections 2395.1-2395.114; exceptions and alternative safety measures are provided in section 2395.6).
  • No electrical power source, including a generator, is allowed to be connected to a premises’ wiring system, or parts of such a system, unless positive means are used to prevent the transmission of electricity beyond the premises’ wiring system or beyond any intentionally segregated parts of the wiring system. Steps to ensure that electricity is not transmitted beyond the premises wiring system would include switching the main power breaker or fuse to the "off" position, however this may not be sufficient in all cases (section 2320.9).
    • Once switched off, employers must lock-out or tag-out the main power breaker or fuse to ensure that they are not inadvertently turned on (section 2320.4).
    • Employers should contact the utility provider before connecting a generator to a premises’ wiring system.
  • See additional information from PG&E on generator safety:

Emergency backup power is required for means of egress lighting, illuminated exit signs, and other lights necessary for illumination needed during an emergency (section 2571.16).

For continuing work during a power outage, employers must ensure that lighting levels meet the minimum requirements for working safely (sections 1523 and 3317).  

Motors capable of causing injury that can automatically restart after power is restored are prohibited (section 2530.43).

Take the following precautions when a power outage occurs:

  • Shut off any electrically powered equipment that was operating when the power went out (section 3203).
  • Stay clear of points of operation and other parts of machinery that could move or cycle unexpectedly when the power returns (section 3203).
  • Turn off any heat-producing equipment to minimize fire hazards when the power returns (section 3203).
  • Ensure flammable gases are purged before relighting pilots of fired equipment (section 3311).

Any work that depends on electrically powered ventilation to prevent harmful or flammable atmospheres should be stopped until ventilation is restored (sections 5141, 5416).

All powered doors must be able to be opened manually in the event of a power failure (section 3235).

October 2019